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‘Subordinate’ meerkat males enjoy one-night stands

Subordinate males are sneaking off to other territories to boost their breeding rates

(Image: Andrew Young, University of Cambridge)

Extra-group mating accounts for 70% of subordinate males’ offspring

(Image: Andrew Young, University of Cambridge)

Meerkats, famous for their cooperative behaviour, live in groups where every member has a socially defined role. But researchers have discovered a degree of insubordination in subordinate male members.

These low-status male meerkats struggle to mate with females in the group where the dominant male reigns. Now, a new study reveals they have a clever tactic to pass on their genes – they are sneaking off in the night to mate with females in other groups.

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Meerkats live in groups of about 30 individuals, and the behaviour of the subordinate males has long been questioned by evolutionary biologists.

“One of the reasons people are drawn to these societies is the apparent cooperation between individuals – subordinate males don’t breed in the groups but they help to rear the dominants’ young,” says Andrew Young at the University of Cambridge in the UK. “But natural selection favours those who maximise their own reproductive success, so it seems paradoxical that these males are helping others.”

Young and colleagues monitored 15 groups of the cooperative meerkat, Suricata suricatta, on ranch land in the southern Kalahari desert. Over a five-year period, the researchers carried out genetic tests to establish the paternity of the pups born during that time.

Brief affairs

Subordinate males made regular trips to other territories during periods of peak female fertility, Young’s team observed. Previously, such forays had been explained as attempts to disperse and find a new territory where they could dominate. However, paternity testing on the pups revealed the males were in fact using these trips to mate and were doing so successfully.

Young says such extra-group mating accounts for 70% of the subordinates’ offspring, and allows the males to breed without permanently leaving their family group. Furthermore, the tactic accounts for as much as a quarter of meerkat young in the whole population.

Previous estimates of subordinate males’ breeding success have not taken into account these extra-group offspring, the researchers say.

“If the subordinates are able to get more reproductive success in other groups, then it gives them another option and may explain why they act as they do,” says Young. “The next step will be to ask why females choose to mate with these subordinate males – males can’t simply force their way into another group and mate with a female, she has to leave the group, so we need to investigate it from a female perspective.”

The most likely explanation, he says, is that such females are unable to mate within their own group – for example, they may be closely related to all the males within it.